Advanced Formula Challenge #12: Results and Discussion 2

Last week I set readers the challenge which can be found here.

Such was the number and variety of responses to this challenge that presenting a detailed breakdown of one such solution – as has been the case for all of the first eleven in this series of challenges – would, I feel, be somewhat inappropriate.

For the majority of these challenges, it could be argued that there has been one solution which is indisputably “better” than the rest. Perhaps such an adjudication can also be made here, though to do so would certainly not be a straightforward exercise. What’s more, to pick just one of the many solutions would be to leave the rest – unfairly in my opinion – left on the sidelines.

As such, I would refer the readers to the many solutions in that post and to enjoy dissecting the varied and wonderful constructions therein. And to simply thank all those – Alex, aMareis, Maxim, John Jairo, sam, Jeff, Lori, Ron, Michael, Christian and XLarium – whose excellent contributions led to such a fruitful and inspiring discussion.

There’s evidently still much to be discovered in the world of worksheet formulas!

Another challenge to follow shortly. Watch this space!

Extracting numbers from a string 2: Consecutive numbers at end 3

This is the second in a series of discussions on the techniques available for extracting numbers from an alphanumeric string. In the first instalment in this series (which can be found here) I looked at extracting consecutive numbers which appear at the start of the string, e.g. 123ABC456.

In this post I will concentrate on techniques for extracting numbers from a string where:

  • The numbers are consecutive
  • The consecutive string of numbers is found at the very end of the string
  • The desired result is to have those consecutive numbers returned to a single cell

As previously, for each of the given solutions, we need to test its soundness in two separate cases: firstly, where there are no numbers elsewhere in the string, e.g. ABC456 and secondly, where there are some numbers elsewhere in the string, either at the start, e.g. 123ABC456, or in the middle, e.g. ABC123DEF456.


Advanced Formula Challenge #7: Results and Discussion 1

Last week I set readers the challenge which can be found here.

This is a trickier problem than it at first appears, and indeed there are several pitfalls which prevent us from using more “standard” techniques to arrive at a solution.

Perhaps the two main (hidden) obstacles, which were not immediately obvious from the examples I gave, are, firstly, the fact that we are prevented from using a construction involving a SEARCH-approach (e.g. by locating occurrences of each substring of the four types *????*, †????*, *????† and †????†, as John Jairo V attempted), since this of course presumes that there is only one occurrence of each of those substring types within our string, a presumption which cannot be made.